PowerSource

I recently wrote an article on lithium ion batteries for electric vehicles (EVs) that was very pro-lithium ion. Basically, lithium ion batteries charge fast and have lots of energy-storage capacity. True, there is the little matter of their tendency to catch fire, but auto makers seems to be sure that the Li+ vendors will shortly (ie, within 5 years) come up with a better version. All in all, I thought it was a very pro-EV article.

However, the article irritated readers who love their existing EVs such as the 2002 RAV4-EV which uses NiMH batteries and has a 100+-mile range on existing – actually 10-year-old – battery technology. These readers don’t accept the premise that all that’s holding back EVs is the battery technology: They’re perfectly happy with their NIMH-powered cars.

I agree, the RAV4-EV sounds like a great car, but unfortunately Toyota stopped making it in 2003. (Sticker price was apparently about $42,000.) As recently as last April Toyota was talking about offering a lithium ion battery in the Prius, but a month later said they were postponing the battery’s introduction due to safety concerns, and for the foreseeable future a NiMH pack is what you’ll get with your Prius.

[There’s an interesting aside in the Toyota article referenced above: The Question (no doubt sparked by Tesla’s recent publicity for its battery pack based on off-the-shelf Li-ion cells) is: “Would arrays of off-the-shelf consumer-type Li-ion batteries work for [hybrids]?” The answer included the fact that early non-US versions of the Prius had battery packs based on D-sized flashlight-batteries, which were later optimized for the present Prius battery pack.]